Tremolo mechanism for organs.



B. R. VAN VALKENBURG.

TREMOLO MECHANISM FOR ORGANS.

APPLICATION FIILED NOV. 4. 1913'. RENEWED ocT. 6.1.916.

1,243,644. I Patented 001. 16, 1917.

Big. 1'

UNITED STATES PATENT orrron.

BURT R. VAN 'VALKENBUBG, OF OAKLAND, CALIFORNIA, ASSIGNOR TO AMERICAN PHOTO PLAYER COMPANY, OF BERKELEY, CALIFORNIA, A CORPORATION OF CALIFORNIA.

Specification of Letters Patent.

TREMOLO MECHANISM FOR ORGANS.

Patented Oct. 16, 191".

Application inea November 4, 1913, Serial No. 799,114. Renewed October 6, 1916. Serial No. 124,207.

To all whom it may concern:

Be it known that I, BURT R. VAN VALKEN- BURG, a citizen of the United States, residing at Oakland, in thecounty of Alameda and State of California, have invented certain new and useful Improvements in Tremolo Mechanism for Organs, of which the follow ing is a specification.

This invention relates to improvements in musical instruments and more particularly to a tremolo device associated with the wind chest of organs.

The principal object of my invention is to produce a device of this class which is effective in operation, simple in construction and adjustable for different pressures and periods.

With these objects in view, my i vention consists in the novel construction and an rangement of parts as herein described and pointed out in the claims hereunto annexed. For a full comprehension of my device reference should be had to the drawings forming a part of this application, wherein Figure 1 is a view in plan of my improved device showing the means for securing adjustment for air pressure, and for period of vibration.

Fig. 2 is a view in side elevation of the device shown in Fig. 1, with a portion of the wind trunk shown in section Referring more particularly to the drawings and denoting corresponding parts throughout the, several views by the same numerals of reference, 1 is a wind trunk supplying air under pressure to the various sets of reeds and pipes, and in the top of this trunk is an' opening 2, preferably oblong or rectanglar in shape. On the upper and lower surfaces of the top of the wind trunk and surrounding the opening 2, are-cemented the-pads 3 of felt or any other suitable material having openings therethrough corresponding in size and shape to the opening 2.

Within the trunk is located a valve 4 which controls the operation of the tremolo. This. valve consists of a horizontal strip 5 of wood or other suitable material which has a width greater than the opening 2, and to which is cemented one or more layers of material such as felt or leather. In the construction here shown, 6 is a strip of felt and 7 a strip of sheep skin. These strips arecentral with the opening in the inner pad 3,

the sheep skin resting thereon and making a tight joint. Strip 5 is hinged to a block 8 in any preferred manner, but I find a flexible leather strip 9 makes the most satisfactory hinge. I find also that the best manner of arranging said leather hinge piece is to form two opposed slots such as 30 and 31, one in the block 8 and the other in the end of the strip 5. The strip or leather 9 is then inserted into the opposed slot and either glued or otherwise secured in place.

Block 8 is attached to the inside of the wind trunk and fastened to it is a helical spring 10 having an arm 11 contacting with the outer end of strip 5, the end of the spring being bent into the form of a shallow hook and resting in a recess 32. A depending arm 12 is attached to strip 5 near its hinged end, and to the end of arm 12 is connected the controlling rod 13 which maybe manually or otherwise operated. Fastened in the upper side of A and extending through openings 2 is a rod 1-1- having a bifurcated end in which is a roller 1 1'. Thus when rod 13 is moved in the direction of the arrow, the valve 4: is lowered from the underside of opening 2 and the tremolo thrown into operation.

The latter consists of a strip 15 hinged to a block 16 as by the leather strip 17 in a manner similar to that described for members 5 and 8. Block 16 is fastened to the outside of the wind trunk, and has attached thereto an upright post 18 which carries a horizontal regulating screw 19 with a felt tipped head 20. As is clear from Fig. 2, member 15 is normally held in the position shown by the roller 1 1 previously mentioned.

Attached to the underside of strip. 15 central with the opening 2, is a layer of felt 21 and a layer of sheep skin 22, these layers being larger than the said opening 2 and when resting on the top or outer pad 3 serve to close said opening. At the hinged end of strip 15 is mounted an L-shaped spring member 23, the upright portion 2A of which extends to a point adjacent the head 20 of the regulating screw and which is adapted to contact therewith.

Intermediate the length of strip 15 is a grooved plate 26 (see Fig. 1) which is attached to 15 by suitable means such as screws 3333 and which serve to clamp thereon, a strip 27, on the end of which is attached a weight 28. The strip 27 is reciprocable on strip 15, its inner end being turned up as clearly shown in Fig. 2 so as to provide a convenient handle or finger piece. It will readily be understood that by moving strip 27 and consequently weight 28, outwardly from the hinge, a greater pressure within the trunk will be required to raise the device from its seat, and hence this weight provides an adjustment for pressure.

By moving the head 20 toward the arm 241 a lesser interval will be required for the rise and fall of the strip 15 and its associated parts this enabling the frequency of the tremolo to be regulated.

The operation is as follows: Rod 13 being moved in the direction of the arrow, valve 4: will be opened which allows the tremolo valve 15 to close the opening 2; the pressure within 1 then overcomes the weight of the valve 15 and causes the said valve 15 to rise. Immediately on the raising of this member, air will escape through the opening thus formed and a reduction in pressure takes place within the trunk 1, causing a reduction in tone volume of the notes being played. This reduced pressure being unable to hold up the member 15, the latter will close opening 2 and the pressure will rise within 1.

The function of spring 23 is to keep the number of vibrations per minute constant irrespective of the pressure in trunk 1. When the pressure is high in the trunk it would be lifted higher than when it is low, and consequently the period would be longer, but by the proper adjustment of 19 a rebound is secured which is proportional to the pressure and keeps the period practically constant.

In this manner I have provided a device which clearly fulfils the objects set forth in the beginning of this specification, and while I have shown the preferred embodiment of the device, it will be understood that minor changes may be made in design and detail of construction and still adhere to the spirit of the same.

Having thus described my invention, what I claim is 1. A tremolo device, comprising in combination, a wind trunk having an opening therein, a supporting member within said valve trunk, a valve hinged to said supporting member, a pad attached to said valve and normally closing the opening in said wind trunk, means for moving said valve to uncover the opening in said wind trunk, a second valve hinged at the outside of said wind trnnk' above said opening, a pad carried by said second valve, means carried by said first 'mentioned valve for normally maintaining the second valve in a raised position, a weight carried by said second valve at its free end and adjustable longitudinally with respect thereto, and means for resiliently arresting the upward movement of said second valve.

2. A tremolo device, comprising in combination, a wind trunk having an opening therein, a valve within said wind trunk and normally closing said opening, a valve on the exterior of said wind trunk for intermittently closing said opening when said first mentioned valve is in its open position, means carried by said first-mentioned valve for normally maintaining said last mentioned valve in the raised position, and means for resiliently arresting the upward movement of said last mentioned valve.

3. A tremolo device, comprising in combination, a wind trunk having an opening therein, a valve within said wind trunk for closing said opening when desired, spring means normally maintaining said valve in the closed position, manually operable means for opening said valve,a second valve on the exterior of said wind trunk for interinittently closing said opening when the said first mentioned valve is in the open position, a weight mounted at one end of said last mentioned valve and adjustable longitudinally with respect thereto, a spring mounted at the other end of said last-mentioned valve, an adjustable stop for said spring mounted on the said wind trunk, said spring and stop serving to limit and resiliently arrest the upward movement of said last-mentioned valve, and means carried by said first-mentioned valve for maintaini said last-mentioned valve in an open position when the former is in its normal closed position.

1. In a tremolo device, the combination of a wind-trunk having an opening in the top thereof and means for intermittently opening and closing said opening comprising a hinged valve, a weight carried by said valve and adjustable longitudinally thereof for adjusting the tremolo for ail pressure within the trunk, a stop, and I. spring carried by said valve and adapted to engage said stop.

5. In a tremolo device, the combination of a wind-trunk having an opening in the top thereof, a valve within the trunk controlling said opening, and means for intermittently opening and closing said opening comprising a hinged valve, a weight wried by said valve and adjustable longitlidinally thereof for adjusting the tremolo for air-pressure within the trunk, a stop, and a spring carried by said valve and adap to engage said stop.

6. In a tremolo device, the combination of a wind-trunk having an opening in the top thereof, and means for intermittently opening and closing said opening comprising a hinged valve, a weight carried by said valve and adjustable longitudinally thereof for adjusting the tremolo for air-pressure within the trunk, an adjustable stop, and a spring carried by said valve and adapted to engage said stop during a portion only of the movement of said valve in its movement away from said openin 7. A tremolo device comprising, in combination, a wind-trunk having an opening therein, a valve Within said wind-trunk and normally closing said opening, a valve on the exterior of said wind-trunk for intermittently closing said opening when said first-mentioned valve is in its open position, and means carried by said first-mentioned valve for normally maintaining said lastmentioned valve in unseated position.

8. A tremolo device comprising, in combination, a wind-trunk having an opening therein, a valve within said wind-trunk and normally closing said opening, a valve on the exterior of said wind-trunk for intermittently closing said opening when said first-mentioned valve is in its open position, means carried by said first-mentioned valvefor normally maintaining said lastmentioned valve in unseated position, and a weight carried by said valve and adjustable longitudinally of the latter, for the purpose set forth.

9. A tremolo device comprising, in combination, a wind-trunk having an opening therein, a valve within said wind-trunk and normally closing said opening, a valve on the exterior of said wind-trunk for intermittently closing said opening when said first-mentioned valve is in its open position, means carried by said first-mentioned valve for normally maintaining said last-mentioned valve in unseated position, means for resiliently arresting the upward movement of said last-mentioned valve, and a weight carried by said last-named valve and adjustable longitudinally of the latter, for the purpose set forth.

10. A tremolo device comprising, in combination, a windtrunk containing an opening, a valve within said wind-trunk and normally closing said opening, a hinged valve on the exterior of said wind-trunk for intermittently closing said opening when said first-mentioned valve is in its open position and arranged to move downwardly in closing said opening, means carried by said first-mentioned valve and normally maintaining said last mentioned valve in open position, a stop, and a spring carried by said last-named valve and adapted to engage said stop during a portion only of its movement to open position.

11. A tremolo device comprising in combination, a wind-trunk containing an opening through which air pressure is permitted to escape, a hinged valve for opening and closing said opening and positioned to move downwardly in closing said opening, a stop, and a spring carried by said valve and adapted to engage said stop during a portion only of its movement in moving away from said opening.

12. A tremolo device comprising in combination, a wind-trunk containing an opening through which air pressure is permitted to escape, a hinged valve for opening and closing said opening and positioned to move downwardly in closing said opening, a stop adjacent the hinged end of said valve, and a leaf-spring carried by said-valve and extending at an angle thereto into position for engaging said stop during a portion only of the movement of said valve in moving away from said opening, to cause the valve to rebound.

In testimony whereof I atfix my signature in presence of two witnesses.

BURT R. VAN VALKENBURG.

Witnesses H. A. VAN VALKENBURG, R. M. OYARZO.

copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. C. 

